If his account has been deactivated there it is probable that he has failed the security check. A few of these reasons could due to having multiple accounts, or maybe living in the US or a problem with his documents.

Hopefully one of the mods, like SoyCD, will be able to give you a more accurate answer. One thing i will say is that PS don't deactivate players accounts without a good reason to.

I'm sorry to hear that your friend's account was closed. However, I'm afraid there's nothing we can do on this matter as the decision of our Security Department is final. Although your friend sent in his ID, he failed to pass our standard security checks and unfortunately, for security reasons we cannot give you more details on this.